Michael A. Peshkin

Mechanical Engineering Department Northwestern University Evanston, Illinois

It is often assumed that the benefit of robots is their strength, speed, or accuracy—qualities that a human operator's "help" can only diminish and that indeed may pose a hazard to him or her. Less recognized is that it may be the robots' interface to computers and information systems that is their primary benefit. Furthermore, even in heavily mechanized environments, people have an important continuing role because of their sensing and dexterity, which cannot be matched or replaced by robots.

Collaborative robots—"cobots"—are a new type of robotic device, intended for direct interaction with a human operator in a shared workspace. Cobots allow a true sharing of control between human and computer. The human operator supplies motive power and exerts forces directly on the payload, while the mechanism of the cobot serves to redirect or "steer" the motion of the payload under computer control. The computer monitors the force (direction as well as magnitude) applied by the operator to the payload. In real time these operator forces can be compared with programmed guiding surfaces, and motion in the direction that the operator pushes can be allowed, disallowed, or redirected. The human operator may be allowed complete freedom of motion of the payload, or in the opposite extreme the payload may be restricted to a single curve through space. Thus, the full versatility of software is available for the production of virtual surfaces and other haptic effects.

At Northwestern, our first application area has been automotive assembly, with the help of General Motors. Unlike body welding and painting, automobile assembly is a worker-intensive process because of the need for human dexterity. Ergonomics issues have become a major concern: even payloads well within human strength limits for lifting can cause significant problems. In response, the

Front Matter (R1-R12)

Biomaterials and Optical Imaging for Biomedicine (1-34)

Advanced Materials (35-62)

Simulation in Manufacturing (63-84)

Robotics (85-110)

Dinner Speech (111-122)

Contributors (123-130)

Program (131-134)

Participants (135-144)

Glossary (145-146)